Bulletin of the Geological Society of Malaysia, Volume 46, May 2003, pp. 137 – 141
Department of Geology, University of Malaya, 50603 Kuala Lumpur
Abstract: The name Sanai Limestone Member is proposed for the thin limestone unit located inside the Jentik Formation, previously known as Unit 4. Stratigraphically it is located near the top of the Jentik Formation, underlain by Mid or Late Devonian red mudstone beds of Unit 3, and overlain by light coloured to black mudstones interbedded with cherts of Unit 5. The lithology consists of planar bedded, grey micritic limestone, with thin shale partings and stylolites. The limestone contains abundant fossils of conodonts, styliolinids, straight cone nautiloids, and trilobites. The occurrence of the conodont Palmatolepis glabra indicates a Late Devonian, Fammenian age. The depositional environment of the Sanai Limestone Member is interpreted to be a deepwater pelagic limestone facies, located at the outer shelf to continental margin region.